98 PROCEEDINGS OF THE AMERICAN ACADEMY 



VII. 



MILK ANALYSES. 



By S. p. Sharples, S.B. 



Presented, Nov. 8, 1876. 



In my former paper on this subject, read before the Academy last 

 Decemlxjr, I gave the residts of the analyses of a number of specimens 

 of milk from the vicinity of Boston. Since that time 1 have iiad occasion 

 to examine critically the method of analysis which I a^as led to adopt 

 by my experiments, as then reported, and the results were so satisfactory 

 that I have extended my investigations further upon the subject of pure 

 milk as produced by cows of different breeds and by the same cow 

 under ditfurent conditions. The pure milk for these experiments was 

 kindly furnished me by Dr. E. L. Sturtevaut, and was in each case 

 drawn under his own supervision. 



The method of analysis followed was &'st to determine the specific 

 gravity, by weighing 100 cc. of the milk : this was then set for cream ; 

 25 cc. were precipitated by acetic add and the sugar determined. 

 Five cubic centimetres were carefully weighed, evaporated to dryness, 

 again weighed, tlie fat dissolved out by benzine, the solids not fat 

 weighed, and then the ash determined by ignition. The caseine was 

 determined by difference, and of course includes all the albumen and 

 other substances of this nature that exist in the solids not fat after the 

 abstraction of the sugar and ash. 



The test analyses, with two exceptions, were made on samples of 

 adulterated milk, which were seized during the past year by the milk 

 inspector of the city of Lynn. 



Analysis No. I. April 1, 1876. 



Cream 5^ 



Sp. Gr 1.020 



